Counterfeit consumer goods, commonly called knock-offs, are counterfeit or imitation products offered for sale. The spread of counterfeit goods has become global in recent years and the range of goods subject to counterfeiting has increased significantly.
Watches are vulnerable to counterfeiting, and have been counterfeited for decades. A counterfeit watch is an unauthorized copy of a part or all of an authentic watch. According to estimates by the Swiss Customs Service, there are some 30 to 40 million counterfeit watches put into circulation each year. It is a common cliché that visitors to New York City are approached on the street by vendors with a dozen such counterfeit watches inside their coats, offered at bargain prices. A counterfeit product may look genuine from the outside and contain sub-standard components. Extremely authentic looking, but very poor quality counterfeit watches can sell for as little as twenty dollars. The problem is becoming more and more serious, with the quality of the counterfeits constantly increasing. Counterfeit watches cause an estimated $1 Billion loss per year to the watch industry.
Authentication solutions that have been used for protection of consumer goods from counterfeiting are often based on marking the item with a specific material, code, or marking, engraving, etc. However, these methods modify the nature and the appearance of the object, and this is often not acceptable in the watch (and other luxury items) industry, where the design of the object and its visual appearance is of paramount importance. Additionally, outer marks may be exposed to copy and environmental factors (wear, dirt, etc.). Also, these methods require an active intervention at the time of manufacturing and, correspondingly an important change of the production process.
A quartz clock is a clock that uses an electronic oscillator that is regulated by a quartz crystal to keep time. This crystal oscillator creates a signal with very precise frequency, so that quartz clocks are at least an order of magnitude more accurate than mechanical clocks. The inherent accuracy and low cost of production has resulted in the proliferation of quartz clocks and watches. By the 1980s, quartz technology had taken over applications such as kitchen timers, alarm clocks, bank vault time locks, and time fuses on munitions, from earlier mechanical balance wheel movements, an upheaval known in watchmaking as the quartz crisis.
Timepieces equipped with quartz movements have dominated the wristwatch and clock market since the 1980s, because of the high Q factor and low temperature coefficient of the quartz crystal they are more accurate than the best mechanical timepieces, and the elimination of all moving parts makes quartz timepieces more rugged and eliminates the need for periodic maintenance. The use of quartz movement is most widespread at the lower end of the market, but not limited to it, and moderately- to very-expensive timepieces fitted with a quartz movement are routinely manufactured and sold.
It is desirable, when assessing the authenticity of a timepiece, to have as much information as possible not only on its outer appearance but also on its inner content. It is furthermore desirable not to have to open the timepiece when checking the authenticity, as the operation requires specialized equipment and procedures, which may impact on the performance and/or integrity of the piece (e.g., water tightness), and which may invalidate the manufacturer's warranty.
It is, therefore, desirable to be able to authenticate a timepiece in a manner that is as non-invasive and as reliable as possible without having to open the timepiece.